[Pythonmac-SIG] Multiple python installation instructions (was IDLE fixes for 2.x and 3.x)

[Tom Bridgman]

I'm doing a presentation on travel next week so I won't try to  
install this until the following week, but this looks *very*  
straightforward and complete.

I don't find this posted on the http://wiki.python.org/moin/MacPython  
or on the FAQ, but it should be.

Thanks,
Tom
On Feb 16, 2009, at 11:07 PM, Ned Deily wrote:

> In article <805E7543-96ED-474F-8059-123B4085C29D at mac.com>,
>  Tom Bridgman <cygnusx1 at mac.com> wrote:
>> Is there a reliable way to install python 3 on a Mac without damaging
>> the resident installation?  Are there 10.4 vs 10.5 issues?
>
> It's easy to install multiple versions and there should be no  
> danger of
> damage.
>
> The python.org 3.0.1 should install on any 10.4 or 10.5 system  
> (actually
> 10.3.x as well, though I don't think that has been tested).  It will
> install the Python framework at /Library/Frameworks/Versions/3.0  
> and it
> will install the folder /Applications/Python 3.0.  In the latter  
> folder
> will be IDLE, Update Shell Profile, and some Extras.  By default, the
> installer will *not* modify your shell profile to add python3.0 to  
> your
> shell $PATH.  You can access 3.0 by launching the 3.0 IDLE.  If you  
> want
> to use python3.0 from a shell without making it your default  
> python, you
> can type in the full path.
>
> /Library/Frameworks/Python.framework/Versions/3.0/bin/python3.0
>
> Or you can create a shell alias to that path (see below).
>
> If you do want to make python3.0 your default python, either edit your
> shell profile to add the path of the framework bin directory to the
> front of your PATH or click on the "Update Shell Profile" command  
> to do
> it for you.
>
> The python.org 2.x installers work exactly the same way, installing  
> into
> /Library/Frameworks/Versions/2.x and /Applications/Python 2.6 (or
> /Applications/MacPython 2.x for 2.5 and earlier)  All versions can
> co-exist with each other and with the Apple-supplied python which  
> lives
> in /System/Library/Versions/Python.framework/2.5 for 10.5 and 2.3 for
> 10.4.  The Apple-supplied python is also linked to from /usr/bin/ 
> python.
> (Like everything else under /System, the python files there are  
> managed
> by Apple and should remain undisturbed.)
>
> So, depending on which pythons you have installed, you could set up
> shell aliases in your shell profile, like:
>
> alias python3.0=\
> "/Library/Frameworks/Python.framework/Versions/3.0/bin/python3.0"
> alias python2.6=\
> "/Library/Frameworks/Python.framework/Versions/2.6/bin/python2.6"
> alias python2.5=\
> "/Library/Frameworks/Python.framework/Versions/2.5/bin/python2.5"
> alias applepython2.5=\
> "/System/Library/Frameworks/Python.framework/Versions/2.5/bin/ 
> python2.5"
> alias macportspython2.5=\
> "/opt/local/bin/python2.5"
> alias finkpython2.5=\
> "/sw/bin/python2.5"
> ...
>
> By default, each instance of python has its own site-packages  
> directory,
> so when installing packages, you need to pay attention to which python
> you are running.  If you are installing by hand, make sure you install
> to the right python by doing something like:
>
>    python3.0 setup.py ...
>
> If you want to use easy_install, you'll probably need to install
> setuptools in each python version.  For the python.org 2.x versions,
> download from and follow the instructions here:
>    <http://pypi.python.org/pypi/setuptools>
> The 10.5 Apple python comes with setuptools pre-installed linked at
> /usr/bin/easy_install.  MacPorts and Fink have setuptools  
> packages.  You
> may want to create aliases to the various easy_installs.  There  
> isn't a
> supported 3.0 version of easy_install yet but people are working on  
> it.
>
> It would be nice to have a more intuitive way to manage the nest of
> pythons.  There will be likely be some discussion and perhaps some  
> work
> on that at the upcoming Pycon.
>
> I'm sure I'm missing some details here but I hope that gives you  
> enough
> to feel comfortable exploring 3.0.
>
> -- 
>  Ned Deily,
>  nad at acm.org
>
> _______________________________________________
> Pythonmac-SIG maillist  -  Pythonmac-SIG at python.org
> http://mail.python.org/mailman/listinfo/pythonmac-sig